Question 829970
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x = youngest
y = mid younger
z = mid older
u = oldest
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u = 3x
y = 21
z = 22
(x + y + z + u)/4 = 27.75
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put the system of linear equations into standard form:
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3x - u = 0
y = 21
z = 22
x + y + z + u = 111
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copy and paste the above linear system in standard form into this matrix-method solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
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solution:
x = youngest = 17
y = mid younger = 21
z = mid older = 22
u = oldest = 51
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Solve systems of linear equations up to 6-equations 6-variables:
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